System and method for standardized modular construction

ABSTRACT

Construction systems and methods of the invention provide building constructions systems which may be assembled, such as for example, by stacking and interconnecting standardized modular blocks between standardized modular posts. The modular posts may be comprised of a sleeve of WPC or other composite material surrounding a reinforced concrete core. The blocks, posts and other components in accordance with the principles of the invention may have a variety of geometries and features. These components may together form the basis of a modular, standardized method and system of constructing dwellings or other buildings.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the National Stage entry from PCT Application No.PCT/US2016/44295 filed on Jul. 27, 2016, which claims benefit of thepriority date of U.S. Provisional Application No. 62/197,529 filed onJul. 27, 2015.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT

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REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTINGAPPENDIX SUBMITTED ON A COMPACT DISC AND INCORPORATION-BY-REFERENCE OFTHE MATERIAL

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COPYRIGHT NOTICE

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BACKGROUND OF THE INVENTION Field of Endeavor:

The present invention relates to systems and methods for construction ofbuildings. More particularly, the invention relates to systems andmethods for constructing buildings using lightweight standardizedmodular blocks capable of withstanding extreme temperatures, weight andforces, are heat and flame retardant, easily transported and easilyassembled.

Background Information:

There are many conventional construction techniques currently in use.Prevalent techniques include wood frame construction, masonry frameconstruction, and light-gauge steel construction. Each of theseconstruction techniques has its own advantages and disadvantages, takinginto consideration various factors such as cost, energy efficiency,durability, aesthetics, difficulty of assembly, and reliance uponspecial tools or components which may be necessary for assembly.

Wood frame construction is currently the most commonly used system forresidential construction. Although wood as a construction materialremains relatively inexpensive, there is growing concern over thequality and quantity of the world's dwindling wood supply. Theseconcerns are particularly acute in countries where native forests havebeen depleted, and reforestation is not practiced. In terms ofdifficulty in assembly, wood frame construction requires a basicknowledge of the structural characteristics and capabilities of avariety of wood products and pieces. The carpenter must also haveadequate skills and experience to employ the appropriate framingtechniques for the structural project at hand. Further, the connectionsystem for the wood components relies upon mechanical fasteners. Thesefasteners must be selected and assembled through the application ofprofessional skills.

Masonry frame construction is still used in many parts of the world,particularly in third-world countries. Masonry construction can beinexpensive if the raw materials are available locally and thecomponents are manufactured close to the building site. Nevertheless,proper assembly of masonry blocks is labor intensive, time consuming,and requires a fairly high level of skill and experience. After theblocks have been assembled, a suitable roof system must still beconstructed and structurally integrated with the upper layer of wallblocks. The point of connection between the walls and the roof iscritical, as high winds may cause a catastrophic separation of the two,if the connection is defective or weak. Masonry construction is alsosubject to damage or complete failure as the result of earthquakes,prevalent in many areas where such construction is commonly undertaken.

A third prior art construction technique which has become more popularin recent years for both commercial and residential structures, islight-gauge steel construction. One advantage of such steel constructionis that is does not directly, at least, have a negative impact on theworld's forests. Also, steel construction is relatively light weight,and pest-proof However, a disadvantage is that steel construction isstructurally similar to wood frame construction, and requires an evenhigher level of construction knowledge and on-site training. Theconnection system for steel structural and panel components is basedentirely upon mechanical fasteners. The assembly of components with suchfasteners must be done properly, through the application of learnedskills and the use of necessary tools.

More recently, yet another building technique, using StructuralInsulated Panels (“SIPS”), has emerged. In a standard SIPS system, apre-manufactured panel replaces the framing, sheathing, and insulationused in prior art construction. Typically, a SIP includes eitherpolystyrene foam or polyurethane foam as material for its core. Thisrigid and dense foam spans the entire thickness of each panel, andprovides a desirably high R-factor. Consequently, structures made fromSIPS are generally stronger, more energy efficient, and offer a higherand more consistent level of quality than structures employing woodframe construction. However, the fastening system used in the standardSIPS system is similar to that used in wood frame construction. Eventhough assembly of the standard SIPS system requires a lower degree ofconstruction knowledge than that necessary for wood-stick framing, itstill requires basic carpentry skills and the use of heavy equipment tomove and locate the large panels which are usually employed.

Wood-plastic composites (WPCs) have been proposed as new buildingmaterials for use in constructing homes, offices, factories, sheds,warehouses, or any other type of edifices, and walls, barriers, floors,decks, or other structure. As compared with wood, WPC profiles or planks200 can have greater durability, lower maintenance costs, and favorableaesthetics, while preserving the use of natural resources. WPC offersimproved dimensional stability, a lower moisture absorption, andresistance to fungi. Wood-plastic composites of the disclosure arerecyclable, and can be used in traditional thermoplastics processingroutes such as extrusion, injection molding, and calendaring.

Thermoplastics which can be combined with wood in the manufacture ofWPCs, which in turn are usable in accordance with the disclosure, caninclude, but are not limited to, High Density Polyethylene (HDPE);Polyvinyl Chloride (PVC); Polypropylene (PP), and Polystyrene (PS). Incomparison to lumber, which shows apparent density of 0.35 g/cc forpines and 0.54 g/cc for red maple, wood-plastic composites typicallyrange within 1 and 1.4 g/cc, depending on the formulation, lending togreater strength and durability.

To reduce weight, WPC can be foamed during production. Provided arequisite amount of strength is retained for a particular application ofthe disclosure, such foamed materials can also be used herein. Whileplastic lumber formulations of the disclosure can make use of almost100% of post-consumer recycled plastics, care must be taken with regardto the total amount of recycled resin used, in order to retain therequisite strength, processability and aesthetics of the final product.

Plastic extrusions can be used to form wall and ceiling panels, andmodular building systems, such as are described in U.S. Pat. No.6,931,803.

WPC can be fabricated with cellulosic fillers melt compounded withpolyolefins and vinyl resins, or other thermoplastic material, takingcare to avoid overheating and damaging the cellulosic material.Wood-plastic composites (WPC) have been used to construct decking andfences, furniture, car parts, and applicances.

The extrusion of WPC is described, for example, in U.S. Pat. Nos.5,938,994 and 6,066,680. Reference may further be had towww.strandex.com.

Log homes, such as are popular in Scandanavian countries and NorthAmerica, are constructed using interlocking wooden planks.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the primary object of the present invention is to providean improved system and method of building construction utilizingstandardized modular units or components that may be rapidly and easilytransported and assembled

In accordance with an embodiment of the disclosure, one type of modularunit or component for building construction comprises an elongate plankdefining a longitudinal axis and having upper, lower, front and backsurfaces. The upper and lower surfaces may have mechanisms forinterconnecting two or more stacked planks which extend substantiallyparallel to the longitudinal axes of the units. The interconnectablemechanisms of an upper surface of a lower unit may be configured to matewith corresponding interconnectable mechanisms on a lower surface of aupper unit. The units or components of the invention may be comprised ofWPC, such as a fabricated composite or aggregate mixture if cellulosicmaterial and plastic.

In various embodiments thereof, the cellulosic material may be 15 to 85wt % of the mixture, 25 to 75% of the mixture, 35 to 65 wt % of themixture or 45 to 55 wt % of the mixture.

In some embodiments, one or more surfaces of the unit may be concave.The concave surface includes an overhanging ledge extending along thelongitudinal axis; the plank further comprises an interior extruded witha honeycomb configuration; the plank further comprises interior wallsextending from a front of the plank to a back of the plank, and from atop of the plank to a bottom of the plank, the walls mutuallyintersecting; the interior walls intersect at 90 degree angles; and/or aplurality of planks are stacked to mate the interconnectable shapes ofupper and lower surfaces of successively vertically stacked planks.

In further variations thereof, the front surfaces of a plank are slopedwith respect to the back surfaces of the plank; an interior of the plankincludes one or more hollow channels extending along the longitudinalaxis filled with an insulating foam; the foam is produced by a reactionof reagents within the one or more hollow channels; the reagents includea soy based material and vegetable oil; the mixture further includes oneor more chemicals which retard degradation of the plank due to sunlight;and/or the mixture further includes one or more chemicals which retard aflammable combustion of the plank.

In another embodiment of the disclosure, a method of building structurescomprises providing an extruded plank defining a longitudinal axis andhaving upper, lower, front and back surfaces, the upper and lowersurfaces having an interconnectable shape extending along thelongitudinal axis, the interconnectable shape of an upper surface of afirst plank shaped to mateably interconnect with the interconnectableshape of a lower surface of a second plank, the plank fabricated with amelted mixture if cellulosic material and plastic.

These and other objects and advantages of the present invention willbecome apparent from a reading of the attached specification andappended claims. There has thus been outlined, rather broadly, the moreimportant features of the invention in order that the detaileddescription thereof that follows may be better understood, and in orderthat the present contribution to the art may be better appreciated.There are features of the invention that will be described hereinafterand which will form the subject matter of the claims appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is a top cross-sectional view of an extrusion die in accordancewith the principles of the invention;

FIG. 2 is a front view of the die of FIG. 1 in accordance with theprinciples of the invention;

FIG. 3 is a perspective view of a plank in accordance with theprinciples of the invention;

FIG. 4 is a side view of the plank of FIG. 3 in accordance with theprinciples of the invention;

FIG. 5 is a side view of two adjacent connecting walls of planks ofFIGS. 3 and 4 in accordance with the principles of the invention;

FIG. 6 is a side view of two adjacent alternative embodiments ofconnecting walls of planks in accordance with the principles of theinvention;

FIG. 7 is a perspective view of intersecting perpendicular walls formedfrom planks in accordance with the principles of the invention;

FIG. 8 is another perspective view of intersecting perpendicular wallsformed from planks in accordance with the principles of the invention;

FIG. 9 is an enlarged perspective view of a notch cut into a plank inaccordance with the principles of the invention;

FIG. 10 is a perspective view of an end of a wall formed from planks inaccordance with the principles of the invention;

FIG. 11 is a perspective view of an alternative embodiment of a plank inaccordance with the principles of the invention;

FIG. 12 is a partial perspective view of an end of a post in accordancewith the principles of the invention;

FIG. 13 is a top plan view of a post in accordance with the principlesof the invention;

FIG. 14 is a perspective view of an alternative embodiment of a wallconstructed from planks in accordance with the principles of theinvention;

FIG. 15 is an enlarged perspective view of section “A” of FIG. 14;

FIG. 16 is an enlarged perspective view of section “B” of FIG. 14;

FIG. 17 is a top plan view of an alternative embodiment of a post and aplank in accordance with the principles of the invention;

FIG. 18 is a perspective view of the alternative embodiment of a post ofFIG. 17 in accordance with the principles of the invention;

FIG. 19 is a perspective view of an alternative embodiment of a plank inaccordance with the principles of the invention;

FIG. 20 is a side elevational view of an alternative embodiment of awall constructed from the alternative embodiments of planks of FIG. 19in accordance with the principles of the invention;

FIG. 21 is a perspective view of the wall of FIG. 20 and accordance withthe principles of the invention;

FIG. 22 is a perspective view of an alternative embodiment of a plank inaccordance with the principles of the invention;

FIG. 23 is a side elevational view of an alternative embodiment of awall constructed from the planks of FIG. 23 in accordance with theprinciples of the invention;

FIG. 24 is another perspective view of the alternative embodiment of aplank shown in FIG. 22;

FIG. 25 is an enlarged perspective view of two adjacent alternativeembodiments of a plank in accordance with the principles of theinvention;

FIG. 26 is an enlarged perspective view of an alternative embodiment ofa plank and a header in accordance with the principles of the invention;

FIG. 27 is a side elevational view of an alternative embodiment of aplank in accordance with principles of the invention;

FIG. 28 is a side elevational view of a header of a wall in accordancewith the principles of the invention;

FIG. 29 is a perspective view of an alternative embodiment of a wallconstructed from the alternative embodiments of planks of FIG. 27aligned consecutively and connected by means of an alternativeembodiment of a post in accordance with principles of the invention;

FIG. 30 is a perspective view of an alternative embodiment of a wallconstructed from the alternative embodiments of planks of FIG. 27arranged perpendicularly and connected by an alternative embodiment of apost in accordance with the principles of the invention;

FIG. 31 is an enlarged perspective view of “A” of FIG. 30;

FIG. 32 is an enlarged perspective view of the alternative embodiment ofthe post of FIG. 30;

FIG. 33 is a top plan view of the alternative embodiment of the post ofFIG. 30 in accordance with the principles of the invention;

FIG. 34 is a perspective view of an alternative embodiment of a wall orcladding constructed from an alternative embodiment of planks inaccordance with principles of the invention;

FIG. 35 is a perspective view of a series of alternative embodiments ofplanks in accordance with principles of the invention;

FIG. 36 is an enlarged perspective view of the end of an alternativeembodiment of a plank of FIG. 35 in accordance with the principles ofthe invention;

FIG. 37 is a side elevational view of an alternative embodiment of aplank of FIG. 35 in accordance with the principles of the invention;

FIG. 38 is an enlarged perspective view of two adjacent connectedalternative embodiments of planks of FIG. 35 in accordance with theprinciples of the invention;

FIG. 39 is a side elevational view of two adjacent connected alternativeembodiments of planks of FIG. 35 in accordance with the principles ofthe invention;

FIG. 40 is an enlarged side view of the interconnection of two adjacentalternative embodiments of planks of FIG. 35 including a seal and a boltin accordance with the principles of the invention;

FIG. 41 is an alternative embodiment of a wall constructed fromalternative embodiments of planks in accordance with the principles ofthe invention;

FIG. 42 is an enlarged perspective view of an alternative embodiment ofa plank used in constructing the wall of FIG. 41;

FIG. 43 is a side elevational view of an alternative embodiment of aplank of FIG. 42;

FIG. 44 is an enlarged view of section “A” of FIG. 41;

FIG. 45 is a side elevational view of an alternative embodiment of aplank in accordance with principles of the invention;

FIG. 46 is a perspective view of an alternative embodiment of a plank inaccordance with principles of the invention;

FIG. 47 is a perspective view of an alternative embodiment of a headerin accordance with principles of the invention;

FIG. 48 is a perspective view of an alternative embodiment of a post inaccordance with principles of the invention;

FIG. 49 is an alternative embodiment of a plank in accordance with theprinciples of the invention;

FIG. 50 is a perspective view of an alternative embodiment of a plank inaccordance with the principles of the invention;

FIG. 51 is a perspective view of a partial building frame constructed inaccordance with the principles of the invention.

DETAILED DESCRIPTION

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not limited in its applicationto the details of construction and to the arrangements of the componentsset forth in the following description or illustrated in the drawings.The invention is capable of other embodiments and of being practiced andcarried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein are for the purpose ofdescription and should not be regarded as limiting.

As required, detailed embodiments are disclosed herein; however, it isto be understood that the disclosed embodiments are merely examples andthat the systems and methods described below can be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present subject matter in virtually anyappropriately detailed structure and function. Further, the terms andphrases used herein are not intended to be limiting, but rather, toprovide an understandable description of the concepts.

The terms “a” or “an”, as used herein, are defined as one or more thanone. The term plurality, as used herein, is defined as two or more thantwo. The term another, as used herein, is defined as at least a secondor more. The terms “including” and “having,” as used herein, are definedas comprising (i.e., open language). The term “coupled,” as used herein,is defined as “connected,” although not necessarily directly, and notnecessarily mechanically.

The term “WPC” as used here in refers to a wood plastic compositematerial. Wood plastic composite materials may be formed from manydifferent materials in various combinations and in various differentratios. They may also include many different additives that may affectthe materials' durability, appearance, flame retardancy, tensilestrength, rigidity, flexibility, melting point change in volume inresponse to change in temperature and other parameters or factors.Unless indicated otherwise, either expressly or by implication, adifferent material may be used in place of WPC so long as thereplacement material has suitable qualities.

As used herein, “components” and “units” are generally usedinterchangeably and refer to individual pieces that when used togetherfacilitate and are incorporated into a system of constructing buildingsas described herein. The components of a system in accordance with theprinciples of the invention may be further categorized into panels,blocks, posts, planks, plates, platforms, lintels and other componentscommonly found in building construction. These various components may bedescribed as modules or as module blocks to indicate that they arediscrete units which may be combined to form a single building orstructure. The components may be considered standardized because eachtype of components generally has similar geometries and have standardsized and shaped interconnection mechanisms.

A system of building construction in accordance with the principles ofthe invention may utilize several different interconnected componentshaving standardized connection means. The various components may beconnected to one another, i.e. interconnected, and less time and withless effort than in any conventional building construction methods.

Formation of a component for use in accordance with the principles ofthe invention from WPC formulation into a desired final geometry may beaccomplished using various techniques. For example, molten WPC may beextruded through a die section to form various components. Duringoptimization of the process, the concentrations of cellulosic materialand other materials forming the WPC mixture may be adjusted as required.

Construction systems and methods in accordance with the principles ofthe invention provide building constructions systems which may beassembled, such as for example, by stacking and interconnectingstandardized modular blocks between standardized modular posts. Themodular posts may be comprised of a sleeve of WPC or other compositematerial surrounding a reinforced concrete core. The blocks, posts andother components in accordance with the principles of the invention mayhave a variety of geometries and features. These components may togetherform the basis of a modular, standardized method and system ofconstructing dwellings or other buildings.

In an embodiment of the disclosure, the units of the modularstandardized building system may have interior cavities such that mayinclude a plurality of hollow spaces within the units. These cavitiesmay be filled with insulating foam or other material, such as forexample foam which is produced by a chemical reaction of two agents, forexample in a Reaction Injection Molding (RIM) process, while the agentsare injected into the hollow spaces. The inclusion of insulating foammay provide a thermal and/or acoustic barrier.

In one embodment, the WPC used in the manufacture of the components orunits of the system may be a blend of polyolefinic thermoplastics,woodflour, and additives which combine to provide structural integrity,flame resistance, and sound and weather shielding, and which can complywith acceptance criteria of applicable building codes.

The following examples, which are exemplary and non-limiting, illustratesome suitable materials for use in some embodiments of the invention foruse in forming the units or components of the modular, standardizedconstruction system.

EXAMPLE FORMULATIONS

One WPC formulation which may be used for manufacturing extruded WPCprofiles of the disclosure, can include a composition of:

from 35 to 65 wt % of a polyolefin, for example a virgin or newlyproduced High Density Polyethylene (HDPE) and/or a blend of virgin HDPE;

up to 10 wt % of recycled post-consumer HDPE, for example recycledbottles;

up to 10 wt % of a mineral filler, for example calcium carbonate ortalc;

from 0.5 to 2.0 wt % of a non-metallic stearate lubricant;

from 1.0 to 3.0 wt % of a maleic coupling agent;

from 0.1 to 0.5 wt % of a thermal stabilizer comprising a blend of anorganophosphate and a hindered phenolic antioxidant, the amount ofthermal stabilizer dependent on the amount of post-consumer recycledcontent;

from 0.1 to 0.5 wt % of an ultraviolet stabilizer comprising a blend ofan ultraviolet absorber and a hindered amine light stabilizer (HALS);and 5 to 15% Halogen-free flame retardants based on monoammonium anddiammonium phosphate.

The foregoing ingredients may be blended, for example in a dryblender,then melt compounded with 35 to 65 wt % of a controlled moisture contentpowdered wood flour. The composition is advantageously formed intopellets in a manner known in the art, for extrusion as planks 200 in asubsequent step. If PVC is used instead of HDPE, a lower percentage ofwood flour or other natural fiber may be advantageous, for example up to30 to 50 wt %. It should further be understood that about 30-75% naturalfiber can be used in various embodiments. It should be understood thatthe foregoing example is a representative formulation that isadvantageously used in carrying out the disclosure, and that there aremany different possible formulations which can be used, depending uponthe particular requirements of the application.

In one embodiment, the wood flour, which may be from either or both ofsoft and hard woods, may have a mesh size of between 40 and 100 mesh,and a moisture content lower than 1%. This may reduce processingfluctuations and equipment wear. Less than about 10 wt % ofpost-consumer polyethylene may be sourced from bottle scrap, in order toobtain highly predictable strength, durability, and appearanceattributes for the final extruded product.

The above composition may be modified in order to advantageously producea desired melting flow index suitable for extrusion. In accordance withthe disclosure, to produce the disclosed profile geometries, flowindexes ranging from 0.1 to 2.0 g/10min (ASTM D-1038) can be achievedwith the disclosed formulation of dry blended ingredients which are thenmelt compounded with treated woodflour in a twin screw extruder. Withoutbeing bound to any particular theory, respective roles of variousconstituents of the formulation are detailed as follows.

The addition of 5 to 15% mineral filler, for example precipitatedcalcium carbonate (CaCO3) and/or talc may provide improved structuralstrength of the extruded profiles, while improving their appearanceimproving the smoothness of the finish Cellulose degradation typicallyoccurs at 200-220 degrees C., and this may be a constraint on WPCprocessing, as cellulose degradation can release volatiles, cause woodbleaching and colour fading, produce unstable flow and outputfluctuations, which may impair the mechanical properties of the WPCproduct. In accordance with the disclosure, the formulation may includespecific chemical additives, including primary and secondaryantioxidants, which can retard thermo-oxidative degradation ofcellulosic materials during extrusion of the WPC formulation. These mayinclude, for example, synergistic blends of organophosphites andhindered phenolic antioxidants which have low volatility and highresistance to hydrolysis. The use of antioxidant additives may promoteproper extrudability of the profiles while avoiding damage due todegradation, which may include discoloration and yellowness.

A light stabilizing additive may protect from damage due to ambientlight, including UV light, and resultant fading and reduced integrity ofthe matrix resin. In an embodiment, the additive can include any or allof the pigment titanium dioxide, for example from 0.5-3 wt %, and lightor UV stabilizers, such as UV absorbers (UVAs), that act by shieldingthe polymer from ultraviolet light, and hindered amine light stabilizers(HALS), that act by scavenging the radical intermediates formed in thephoto-oxidation process. Examples include benzophenones andbenzotriazoles, or blends of these, as described in U.S. Pat. No.8,901,209.

To improve interface properties between the cellulosic filler and thepolyethylene co-polymer, a maleic coupling agent, for example maleicanhydride with a melt flow index within the range of 20 to 100 grams/10min, may be added. This may produce, for example, maleic anhydridegrafted polyolefins with a melt flow index ranging from 100 to120g/10min). (ASTM D 1238-190° C./2.16 k) with maleic graft indexranging from 1 to 3.0%. The coupling agent may improve wettability ofthe cellulose filler by reducing the surface tension at the wood-plasticinterface, improving mechanical strength and resistance to delaminationand moisture uptake by the composite. This may result in improveddimensional stability of the extruded profile embodiments by reducingmoisture uptake during a service life of the planks 200, posts 240, orother extruded WPC components of the disclosure.

Improved filler dispersion, and wetting of the filler surface may beachieved by using a lubricant, for example a non-metallic steariclubricant. The result is improved processability and rheology for higherextrusion throughput. Lubricants can also include a blend of complexmodified fatty acid esters.

Fire retardancy, for example to meet IBS standards, can be improved bythe addition of halogen-free flame retardants and smoke suppressants,such as zinc borate or a molybdenum derivatives.

Organic or other pigments may be added for improved aesthetics andlong-term proof resistance to colour fading.

Resistance to degredation by insects may be improved by the addition ofa biocide, for example zinc borate, advantageously with provenresistance to termites, mildew and fungus.

Example Processing

Using the foregoing example formulation, or other suitable WPCcompositions, components cmay be produced in accordance with thedisclosure using the following process. Processing of pelletized woodplastic composite is performed using a counter-rotating conical twinscrew extruder, having a screw diameter front and rear of 92 and 188 mm,respectively. Five heating zones are provided in the barrel, anddegassing means are positioned at half of the length of the screws. Thecounter-rotating twin screw extruder used in the invention was designedto meet throughput rates up to 2,600 lbs/hr. The screws have threedistinct zones: feeding, conveying, and metering, which are designed toprovide high head pressure capabilities and high torque for gentleplastification of the melt to feed the die shown in FIG. 1. Theequipment is selected for heat and shear sensitive materials such asWPC. More particularly, it is desired to have a narrow residence time inorder to produce optimal melt conditions for feeding the die with ahomogeneous and continuous flow melt.

In accordance with the disclosure, it may be advantageous to have a melttemperature of about 150 to 170 degrees C, and a die temperature of 130to 180 degrees C. Screw speed may be between about 10 and 20 rpm, with amelt pressure of between 5 and 15 Mpa.

An embodiment of tooling to provide the final geometry of a profile ofthe disclosure is shown in FIG. 1. Dual cavity extrusion dies may beused for manufacturing the extruded profile geometries depicted in someof the Figures. Flow channels 112 may be designed to promoting abalanced and evenly distributed flow throughout the cross section of thetool, with a homogeneous heating distribution within the die. Thispromotes controlled viscosity and a balanced downstream molten flow intodie, to accurately produce the final profile geometry of the extrudedplank.

Referring now to FIG. 1, a transverse cross-section of an extrusion die110 of the disclosure reveals two cavities 108 for simultaneouslyproducing two extruded plancks 200. In this example, the plancks 200formed using die 110 may have a convex external geometry, as can be seenin FIG. 2. Runners or flow channels 112 are designed to promote abalanced, even flow through and out of die 110. Heaters 114 maintain anoptimal temperature distribution of the composition as it moves throughchannels 112 and past the die lips 118, in order to control a viscosityof the composite melt to balance a downstream flow to produce a correctfinal geometry of the extruded profile plank.

The plank 200 shown in FIGS. 3 and 4 provides one type of component thatmay be useful for a system of construction in accordance with thepresent invention. A plank 200 may have a facing surface 203, a rearsurface 205 and two opposite connecting surfaces 210 and 211. The facingsurface 203 may typically be the surface of the plank positioned on theoutside of a wall or other surface built from planks and may be the mostaesthetically pleasing. In this embodiment, the facing surface 203 isslightly convex. If several planks 200 are aligned parallel to oneanother and engaged by means of their connecting surfaces to 10, it maygive the appearance of several logs or other rounded objects aligned orstacked. Planks 200 may be used to form walls, ceilings, roofing, floorsor other surfaces. Planks 200 may also be formed sufficiently thick thatthey may be used to serve simultaneously as the framing for a wall aswell as its cladding, insulation and other components. Optionally, therear surface 205 may also serve as a facing surface for the interior ofa building or other structure. The connecting surfaces 210 and 211 mayinclude complementary attachment mechanisms.

FIG. 5 shows an enlarged view of corresponding complementary connectingsurfaces 210 and 211. Connecting surface 211 may include two ridges 224.Each of the ridges 224 may include a small rib 228 on each side. Theridges 224 and their ribs 228 may extend all or part of the longitudinallength of a plank 200. The connecting surface 210 may have two channels229 corresponding to the two ridges 224. Each of the channels 229 mayinclude a small groove 229 on either side corresponding to the ribs 228.The ridges 224 and channels 226 may be sized such that they are surfaceslies substantially flush when the ridges 224 are inserted into thechannels 226. The ribs 228 and the grooves 229 may be slightly angledsuch that the ribs 228 may be securely snapped into place. This maysecure two adjacent planks 200 securely to one another.

FIG. 6 shows alternative embodiments of two connecting surfaces 240 and241. The connecting surface 241 may include two ridges 244 and theconnecting surface 240 may include two channels 246. The two channels246 may include two grooves 250. In this embodiment, the ridges 244 mayalso have two grooves 248 instead of ribs like the one shown in FIG. 12.The ridges 244 may be sized slightly smaller than the channels 246 toprovide a small space between the two structures when the ridges 244 areinserted into the channels 246. A glue, which may have elastomericproperties when dry, may be used along the connecting surfaces 240 and241. The grooves 248 and 250 along both the ridges 244 and channels 246may retain some of the adhesive to better secure two adjacent planks 200together.

Numerous other complementary connecting surfaces are known in the artand many may be suitable. For example ridges and channels without ribsor grooves may be used. Connecting mechanisms may utilize interferencefit, snapping into place, nuts, bolts, screws, rivets and other devices.

Planks 200 of any length may be extruded, but may typically be about 20feet long for convenience in storage, packaging, and/or distribution.The longitudinal length of the plank 200 may be defined by the endsurfaces 209. As may be seen from viewing and in surface 209, theinterior 207 of the plank 200 has been shaped to form a plurality ofcavities 220 parallel to the longitudinal axis of the plank. Thesecavities 220 may be defined by interior walls 222 that are parallel tothe connecting surfaces 210 and several interior walls 223 that may besubstantially perpendicular to interior walls 222. The perpendicularrelationship of interior walls 222 and interior walls 223 results in thecavities 220 having a substantially rectangular cross-section and havinga substantially parallelepiped shape. The cavities 220 may generallyextend the entire longitudinal length of the plank 200. When as here oneof the surfaces is convex or other shape, some of the channels may berectangular or curved or have other geometries. The placement ofcavities 220 with in the planks 200 may reduce their weight and theamount of material required to form them. The honeycomb structure mayallow this reduction in weight and materials without sacrificingstrength.

Planks may have any length, and that the lengths illustrated in theFigures of this disclosure are not to be construed as limiting. Further,planks may have any length and width, subject to applicable constraintsof production and use.

Referring now to FIGS. 7 -10 it may be seen that the planks 200 may beconnected in a configuration providing a building resembling a log home.As explained above, planks 200 may have a facing surface 203 which isconvex. A notch 282 may be removed from plank 200, for example bycutting or stamping. In the partly exploded view of FIG. 7, it may beseen that notch 282 of plank 200 may receive an upper portion, forexample about one half, of a plank 200 positioned perpendicularly. Thisplank 200 may be similarly notched to receive a similar portion of asuccessive plank 200. The lower portion of FIG. 7 illustrates severalplanks 200 thus interconnected to form two walls and a corner of abuilding. Any of a variety of means can be used to more fixedly connectthe planks interwoven and interconnected in this manner, includingadhesive, screws, bolts, rivets, straps, braces, ultrasonic welding,melting, or any other known or hereinafter developed method. In theillustration, planks 200 are interconnected to form perpendicular walls230. Notches 282 can be cut on a bias angle to enable any particularangular disposition of planks 200. In this manner, a building may beconstructed relatively easily, but also securely and having desirableproperties.

A series of walls 230 formed by interconnected planks 200 may form adwelling with the appearance of a log home, or any other structure,including a shed or barn, or any other building, or an open structure,such as a fence, corral, or barrier, for example using planks 200 toform walls disposed in alternating directions.

End caps 284 are shown in FIGS. 8-10 and may serve, in part, to coverand conceal the interior of the planks 200, which may include aninterior honeycomb structure. This may form a more finished appearance,and may further protect the interior of the planks 200. End caps 284 mayprevent plants, animals, rain and water, fire, debris and other thingsfrom entering into an interior of planks 200. End caps 284 may be sizedand dimensioned to cover the ends of any of the plank 200 alternativeembodiments disclosed herein. In FIGS. 8-10, it may be seen that endcaps 284 may have a scalloped shape to conform to and seal anintersection of the notched and nested planks 200. The embodiment shownin FIG. 10 may include rounded profiles on opposing sides thereof, tobetter mimic the appearance of a log on protruding ends of planks 200,particularly where plank 200 is flat on a side opposite a rounded,log-like side.

FIG. 11 shows an alternative embodiment of a plank 300. The plank 300may be constructed in a manner similar to plank 200 above. It mayinclude interior walls 322 perpendicular to interior walls 323, whichmay thereby form cavities 320. The plank 300 may also include a facingsurface 303, rear surface 305 and two connecting surfaces 310 and 312.The facing surface 303 may be textured or otherwise designed to be asaesthetically pleasing. Each of the planks 300 may have a length definedby two end surfaces 309. The end surfaces 309 may be substantially flat.

FIGS. 12 and 13 show a modular standardized post 350. The post 350 mayinclude one or more flat facing surfaces 352 and one or moreinterconnecting surfaces 354. Facing surfaces 354 may include aconnecting bed 342 defined by one or more connecting lips 340. Theconnecting surfaces 310 and 312 may have connecting mechanisms similarto those shown in FIGS. 5-6. During construction of a building or otherstructure, the planks 300 may be attached side-by-side and there endsurfaces 309 may be placed within connecting beds 342 of two posts 350,as shown in FIGS. 13-15.

FIG. 14 shows planks 300 stacked vertically to form two wall sections332 and 334 joined by a connecting post 350. Each wall 332 and 334 areshown as constructed using six planks 300 for clarity in theillustration. It may be noted that for practical, design flexibility,and strength considerations, the height of the planks 300 may result instacking 13-14, or more planks 300, in order to form a wall, dependingupon the height of each plank 300. Another plurality of planks 300 maybe inserted into the connecting bed 342 of a post 350 on an adjacentside of the first post 350. The posts 350 may have other configurationswhich form different angles, and different numbers of connections. Aplurality of posts 350 may join walls 330 to form an enclosing perimeteror other structure.

FIG. 15 shows in detail section “A” which includes an end portion ofplank 300 inserted into a connecting bed 342 of a post 350. In oneembodiment, plank 300 may be retained within a connecting bed 342 by aninterference fit between planks 300 and the lips 340. In anotherembodiment, an adhesive may be used to connect post 350 to plank 300.Other methods of connection may also be used. Post 350 may include anynumber of connecting beds adapted to join any number of wall sections230. FIG. 16 shows in detail section “B” which shows connecting surfaces310 and 312 of adjacent stacked planks 300 having there end surfaces 309flush so that they may be inserted into a connecting bed 342.

The post 350 may include a hollow exterior comprised of WPC or a similarmaterial and may include one or more aesthetically pleasing surfacessuch as facing surfaces 352. In other embodiments, post 350 may be madeof another material, and may have increased strength relative to planks200. The posts 350 may be constructed to support a load, such as a roof,or to provide additional strength to connected walls, for example tobear forces imparted by a high wind load. For example, a post 350 may beformed with steel reinforced concrete, or metallic tubing or channels.Post 350 may be larger or smaller than depicted. Post 350 may optionallyhave a triangular profile, or a partly circular profile.

During construction, it may be desirable to first erect one or moreposts 350 at a desired location and fill the post 350 with reinforcedconcrete, for example including rebar. Planks may then be successivelystacked on top of one another as they are slid down the connecting bedsof the posts.

FIGS. 17 and 18 show an alternative embodiment of a post 380 for use inthe present invention. Post 380 may include one or more facing surfaces382 and 384 and two or more connecting surfaces 386. Each connectingsurface may include a connecting bed 388 defined by a short lip 390 anda complex lip 391. The complex lip 391 may include an interior groove392. This post may be utilized to form a more secure engagement with aplank 394 having a bulge 396. In this embodiment, the plank 394 onlyincludes one bulge 396. Optionally, the post 380 may include two complexlips 391, each having an interior groove 392 for connection to a plankhaving a bald on each side.

FIG. 19 shows an alternative embodiment of a plank 400. As with theother planks, plank 400 may include a facing surface 403, a rear surface405 and two connecting surfaces 410 and 412. Plank 400 may also includean interior honeycomb structure and may have a length defined by two endsurfaces 409. In this embodiment, plank 400 includes a facing surface403 that is concave rather than convex.

FIG. 20 shows two of the planks 400 of FIG. 19 connected by engagementof their respective connecting surfaces 410 and 412. FIG. 21 shows awall 430 formed by connecting several planks 400. The wall 430 may beplaced between two posts to secure it in place in a structure.

FIGS. 22-24 show planks 500 individually and interconnect. Plank 500 mayhave a facing surface 503 that may give the appearance of cladding. Alower lip 515 may extend partially over the upper connecting surface 512of a lower plank 500 win it engages the lower connecting surface 510 ofthe upper plank 500.

Planks 500 are interconnected along top connecting surface 510 andbottom connecting surface. Plank 500 may include a slanted surface 503from which a lip 515 extends downward covering the interface between thebottom connecting surface 510 and the top connecting surface 512 of theplank 500 below it.

Ridges 513 on top connecting surface 512 may be partially compressedduring an interference fit into the channels 514 on the lower connectingsurface 510 and 514, to form a water tight seal. Additionally oralternatively, a resilient gasket may be intercalated between theconnecting surfaces 510 and 512 or at another location to form awatertight and/or gas tight seal between connected planks 500. In allembodiments, a connection between planks, a wall and/or a post may becarried out using clips, screws, bolts, adhesive, or other methods.

FIGS. 25-33 show alternative embodiments of planks 600 and posts 650 inaccordance with the principles of the invention. Like other planks,planks 600 and have a first connecting surface 610 having one or moreridges 613, and a second connecting surface 612 having one or morechannels 614 configured to interface with the ridges 613. As with otherembodiments, the ridges 613 and channels 614 may engage by means of aninterference fit and/or the use of glue or adhesives and may includeadditional structures as explained in FIGS. 5 and 6.

Multiple stacked planks 600 may be used to form a wall 630. A wall 630may include a header 690. A header 690 may include ridges 692 such thatit may securely engage a connecting surface 610 of a plank 600. Theheader 690 may also include flat facing surfaces 694 and a planar, flatupper surface 691.

Walls 630 may be joined consecutively using a post 650, or may be joinedin a perpendicular configuration using a post 670. A post 670 mayinclude connecting beds 674 between facing surfaces 673. The post 670may also define one or more interior cavities 672 that may be filledwith concrete, reinforced concrete or other material.

FIGS. 37-40 show another alternative embodiment of planks 700 designedto imitate cladding. Plank 700 may be used to construct a wall 730, oralternatively may be used to form a façade over another wall. The plank700 may include a slanted facing surface 703 that may include a patternsuch as for example a series of parallel horizontal lines. The plank 700I also include one or more interior cavities 720 that may runlongitudinally along the width of the plank. The plank 700 may have atop connecting surface 710 and a bottom connecting surface 715. The topconnecting surface may include a ridge 711 complementary to a channel718 in the bottom connecting surface 715 of the plank 700. The channel718 may also include a groove 719 in which a gasket or seal 750 may behoused. The use of seal 750 may result in the wall being impermeable.Optionally, a screw or bolt 752 may be placed through the plank 700 andextends out the back surface 708 and into a wall covered by the planks700.

FIGS. 41-44 show another alternative embodiment of planks 800 that maybe used as a façade on another wall or for a similar purpose. A plank800 may include a facing surface 803, a top connecting service 810 and abottom connecting surface 812. The top connecting surface 810 mayinclude a ridge 818 configured to fit within a channel 815 on the bottomconnecting surface 812. Optionally, a seal 850 may be incorporated intothe connection between the ridge 818 and the channel 815. The topconnecting surface 810 may optionally include a cover 817 designed to beflush with the back portion of bottom connecting surface 812.

Compression Test Loading

Planks in accordance with the principles of the invention may be testedfor resistance to compression loading. A WPC composition suitable foruse in the present invention may include 30-50% natural fibers, up to10% mineral filler, 3-8% lubricants, no coupling agent, 2-6% color andU/V protection, 1-3% heat stabilizer, and up to 2% biocide, with theremainder comprising a PVC polymer.

A plank 900 shown in FIG. 45, measuring 15.5 cm wide, 19 cm tall, andhaving one half to 1 cm thick walls and constructed of the materialdescribed immediately above may be compression tested in all threecardinal directions. Speed for the test may be conducted according toASTM methods D695-10 Standard Test Method for Compressive Properties ofRigid Plastics at 1.3 mm/min. The segment was fully covered at the topand bottom, and loaded to failure at a constant crosshead speed per ASTMD 695-10 Section 9. Load-deflection data was recorded at 0.5 secintervals during testing.

In addition to testing, Euler buckling loads were calculated as shown inTable 2, using the thickness of the column sections and their lengths.The moment of inertia was calculated using the formula I=(Lt³/12). Eulerbuckling load for a single column was determined using the equationP=Nπ²EI/h², where where: I=the moment of inertia for the column section,L=the length of the test specimen, t=the thickness of the individualcolumn section, P=the Euler buckling load for the individual column,E=Material modulus of elasticity, and h=the height of the columnsection.

The total cross section buckling capacity was calculated as the sum ofthe column capacities. A modulus of elasticity of 4140 MPa (about600,000 psi) was estimated for a PVC based wood-plastic composite, and2070 MPa (about 300,000 psi) for a polyethylene based wood-plasticcomposite. These figures were used for calculations of the ultimatebuckling load if the structure failure occurs in a brittle manner, asobserved during the test performance. Test results are shown in Table 1.

TABLE 1 Compression Test Results Gross Supporting Max- Strength-Strength- Spec- Surface Column min- imum Gross Supported imen Orien-Area imum Area Load Area Area # tation (cm²) (cm²) (kN) (MPa) (MPa) 1 X210.49 54.00 98.86 4.70 18.31 2 Y 281.42 52.19 84.54 3.00 16.20 3 Z113.61 ** 440.96 38.31 N/A

TABLE 2 Euler Buckling Analysis kN Type Note X-Direction Ptotal = 4864.0PVC for fixed-fixed end conditions Ptotal = 1216.0 PVC for fixed-fixedwith side Ptotal = 2432.0 Polyethylene for fixed-fixed end conditionsPtotal = 608.0 Polyethylene for fixed-fixed with side Y-Direction Ptotal= 2299.2 PVC for fixed-fixed end conditions Ptotal = 574.8 PVC forfixed-fixed with side Ptotal = 1149.6 Polyethylene for fixed-fixed endconditions Ptotal = 287.4 Polyethylene for fixed-fixed with side

Comparison of the test results with the Euler Buckling analysisillustrate that much greater strength is available within the design ofplank 900. The plank segment 900 of FIG. 45 is a pre-productionprototype. The planks described in FIGS. 1-44 may be suitable for use inconstruction if they exhibit the same results using the test methodsdescribed herein. Such planks may have more than enough strength toserve as wall members for dwellings, offices, storage facilities orother structures. More particularly, the results show that the planksare capable of supporting more than their own stacked weight, and caneven be used as load bearing members of such structures, and that theyhave sufficient strength for many other applications.

The use of planks and posts in accordance with principles of theinvention may have advantages in terms of assembling simplicity, reducedscrap in construction sites, and uses renewable resources in itsmanufacturing process that qualifies for green building certificationLEEDS—Leadership in Energy & Environmental Design. The disclosure canprovide modular building systems that are produced from renewableresources, and which contain renewable and recycled materials, incompliance with existing building construction recommendations, such asthe International Code Council (ICC) and International Building Code(IBC). Furthermore, the proposed building systems contribute tosubstantial reduction of materials used in construction sites, and areeligible for points and verifiable attributes within the Green BuildingStandards, in accordance to ICC-ES Evaluation services.

FIG. 46 shows an alternative embodiment of a plank 910 similar to inferuse with planks 500. FIG. 47 shows an alternative header 920 that may beused on top of or below walls constructed of planks in accordance withthe invention. Optionally, a header 920 may also be used for the ends ofwalls. FIG. 48 provides an alternative embodiment of a post 930 that mayengage ridges or channels on the ends of or on top of walls constructedfrom planks as disclosed herein.

FIG. 49 shows a plank 940 similar to the planks shown in FIGS. 5-10 butdoes not include an interior honeycomb structure. Plank 940 may beuseful for creating a façade over an existing wall. Optionally, plank940 may be used as a post or as a header for a wall. FIG. 50 shows aplank 950 that may include a few channels 952 but otherwise be moresolid than the other planks or posts shown herein.

FIG. 50 shows an initial stage of construction of a frame 1000 for abuilding in accordance with the principles of the invention. First,pilings 1006 are inserted into the grounds in accordance with typicalconstruction practices. The pilings 1006 may be concrete, reinforcedconcrete or other materials used in the art. Next, posts 1010 are fittedover the pilings 1006 by sheathing the pilings 1006 using posts asdescribed herein. Footers 1004 may be placed between the posts 1010after the posts 1010 have been erected. The headers 1008 may beincorporated into the frame before or after planks have been inserted toform walls.

All references cited herein are expressly incorporated by reference intheir entirety. It will be appreciated by persons skilled in the artthat the present disclosure is not limited to what has been particularlyshown and described herein above. In addition, unless mention was madeabove to the contrary, it should be noted that all of the accompanyingdrawings are not to scale. There are many different features to thepresent disclosure and it is contemplated that these features may beused together or separately. Thus, the disclosure should not be limitedto any particular combination of features or to a particular applicationof the disclosure. Further, it should be understood that variations andmodifications within the spirit and scope of the disclosure might occurto those skilled in the art to which the disclosure pertains.Accordingly, all expedient modifications readily attainable by oneversed in the art from the disclosure set forth herein that are withinthe scope and spirit of the present disclosure are to be included asfurther embodiments of the present disclosure.

Whereas, the present invention has been described in relation to thedrawings attached hereto, it should be understood that other and furthermodifications, apart from those shown or suggested herein, may be madewithin the spirit and scope of this invention. Descriptions of theembodiments shown in the drawings should not be construed as limiting ordefining the ordinary and plain meanings of the terms of the claimsunless such is explicitly indicated.

As such, those skilled in the art will appreciate that the conception,upon which this disclosure is based, may readily be utilized as a basisfor the designing of other structures, methods and systems for carryingout the several purposes of the present invention. It is important,therefore, that the claims be regarded as including such equivalentconstructions insofar as they do not depart from the spirit and scope ofthe present invention.

1. A modular standardized system for building construction comprising:One or more planks having a facing surface, a rear surface, and twoconnecting surfaces, wherein the connecting surfaces are configured toengage one another and may form a wall; Optionally including one or moreposts between walls that are parallel or perpendicular to each other.